It is known to use some type of fuse holder to mount standard circuit breakers in distribution units for supplying electric current to radio base stations and for re-charging the batteries of said stations. This type of fuse holder is often designed to carry and correctly connect a circuit breaker to an input power supply bar, an alarm board, and to establish an output cable connection in a distribution unit. The vertical space required to house this type of connector means with circuit breakers carried by a fuse holder is determined by the vertical extension of three mutually overlying modules.
FIG. 1 shows how three standard circuit breakers mounted in a fuse holder are connected to an input power bar, an alarm board, and upper output cable connections.